x86, apic: Make apic drivers static

Apic probe now looks at the apic drivers listed in the
.apicdrivers section. Remove apic_probe[] and make each apic
driver static.

Signed-off-by: Suresh Siddha <

x86, apic: Make apic drivers static

Apic probe now looks at the apic drivers listed in the
.apicdrivers section. Remove apic_probe[] and make each apic
driver static.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: gorcunov@openvz.org
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110521005526.341718626@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86, apic: Introduce .apicdrivers section to find the list of apic drivers

This will pave the way for each apic driver to be self-contained
and eliminate the need for apic_probe[].

Order in which a

x86, apic: Introduce .apicdrivers section to find the list of apic drivers

This will pave the way for each apic driver to be self-contained
and eliminate the need for apic_probe[].

Order in which apic drivers are listed in the .apicdrivers
section is important, as this determines the apic probe order.
And this is enforced by the ordering of apic driver files in the
Makefile and the macros apic_driver()/apic_drivers().

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: gorcunov@openvz.org
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110521005526.068775085@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86, x2apic: Move the common bits to x2apic.h

To eliminate code duplication.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: steine

x86, x2apic: Move the common bits to x2apic.h

To eliminate code duplication.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.591426753@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86, x2apic: Minimize IPI register writes using cluster groups

In the case of x2apic cluster mode we can group IPI register
writes based on the cluster group instead of individual per-cpu
destinatio

x86, x2apic: Minimize IPI register writes using cluster groups

In the case of x2apic cluster mode we can group IPI register
writes based on the cluster group instead of individual per-cpu
destination messages.

This reduces the apic register writes and reduces the amount of
IPI messages (in the best case we can reduce it by a factor of
16).

With this change, the cost of flush_tlb_others(), with the flush
tlb IPI being sent from a cpu in the socket-1 to all the logical
cpus in socket-2 (on a Westmere-EX system that has 20 logical
cpus in a socket) is 3x times better now (compared to the former
'send one-by-one' algorithm).

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.512271057@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86, x2apic: Track the x2apic cluster sibling map

In the case of x2apic cluster mode, we can group IPI register
writes based on the cluster group instead of individual per-cpu
destination messages.

x86, x2apic: Track the x2apic cluster sibling map

In the case of x2apic cluster mode, we can group IPI register
writes based on the cluster group instead of individual per-cpu
destination messages.

For this purpose, track the cpu's that belong to the same x2apic
cluster.

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.421800999@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86, x2apic: Remove duplicate code for IPI mask routines

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: yinghai@kern

x86, x2apic: Remove duplicate code for IPI mask routines

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.337024125@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86, apic: Use probe routines to simplify apic selection

Use the unused probe routine in the apic driver to finalize the
apic model selection. This cleans up the
default_setup_apic_routing() and thi

x86, apic: Use probe routines to simplify apic selection

Use the unused probe routine in the apic driver to finalize the
apic model selection. This cleans up the
default_setup_apic_routing() and this probe routine in future
can also be used for doing any apic model specific
initialisation.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: steiner@sgi.com
Cc: yinghai@kernel.org
Link: http://lkml.kernel.org/r/20110519234637.247458931@sbsiddha-MOBL3.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: Replace apic->apicid_to_node() with ->x86_32_numa_cpu_node()

apic->apicid_to_node() is 32bit specific apic operation which
determines NUMA node for a CPU. Depending on the APIC
implementation,

x86: Replace apic->apicid_to_node() with ->x86_32_numa_cpu_node()

apic->apicid_to_node() is 32bit specific apic operation which
determines NUMA node for a CPU. Depending on the APIC
implementation, it can be easier to determine NUMA node from
either physical or logical apicid. Currently,
->apicid_to_node() takes @logical_apicid and calls
hard_smp_processor_id() if the physical apicid is needed.

This prevents NUMA mapping from being queried from a different
CPU, which in turn makes it impossible to initialize NUMA
mapping before SMP bringup.

This patch replaces apic->apicid_to_node() with
->x86_32_numa_cpu_node() which takes @cpu, from which both
logical and physical apicids can easily be determined. While at
it, drop duplicate implementations from bigsmp_32 and summit_32,
and use the default one.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Pekka Enberg <penberg@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-13-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: Kill apic->cpu_to_logical_apicid()

After the previous patch, apic->cpu_to_logical_apicid() is no
longer used. Kill it.

For apic types with custom cpu_to_logical_apicid() which is also
used fo

x86: Kill apic->cpu_to_logical_apicid()

After the previous patch, apic->cpu_to_logical_apicid() is no
longer used. Kill it.

For apic types with custom cpu_to_logical_apicid() which is also
used for other purposes, remove the function and modify its
users to do the mapping directly.

#ifdef's on CONFIG_SMP in es7000_32 and summit_32 are ignored
during conversion as they are not used for UP kernels.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: eric.dumazet@gmail.com
Cc: yinghai@kernel.org
Cc: brgerst@gmail.com
Cc: gorcunov@gmail.com
Cc: penberg@kernel.org
Cc: shaohui.zheng@intel.com
Cc: rientjes@google.com
LKML-Reference: <1295789862-25482-7-git-send-email-tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system

John Blackwood reported:
> on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded),
> and 32 bit (x86) kerne

x86, irq: Allow 0xff for /proc/irq/[n]/smp_affinity on an 8-cpu system

John Blackwood reported:
> on an older Dell PowerEdge 6650 system with 8 cpus (4 are hyper-threaded),
> and 32 bit (x86) kernel, once you change the irq smp_affinity of an irq
> to be less than all cpus in the system, you can never change really the
> irq smp_affinity back to be all cpus in the system (0xff) again,
> even though no error status is returned on the "/bin/echo ff >
> /proc/irq/[n]/smp_affinity" operation.
>
> This is due to that fact that BAD_APICID has the same value as
> all cpus (0xff) on 32bit kernels, and thus the value returned from
> set_desc_affinity() via the cpu_mask_to_apicid_and() function is treated
> as a failure in set_ioapic_affinity_irq_desc(), and no affinity changes
> are made.

set_desc_affinity() is already checking if the incoming cpu mask
intersects with the cpu online mask or not. So there is no need
for the apic op cpu_mask_to_apicid_and() to check again
and return BAD_APICID.

Remove the BAD_APICID return value from cpu_mask_to_apicid_and()
and also fix set_desc_affinity() to return -1 instead of using BAD_APICID
to represent error conditions (as cpu_mask_to_apicid_and() can return
logical or physical apicid values and BAD_APICID is really to represent
bad physical apic id).

Reported-by: John Blackwood <john.blackwood@ccur.com>
Root-caused-by: John Blackwood <john.blackwood@ccur.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1261103386.2535.409.camel@sbs-t61>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

show more ...

x86: Fix MSI-X initialization by using online_mask for x2apic target_cpus

found a system where x2apic reports an MSI-X irq initialization
failure:

[ 302.859446] igbvf 0000:81:10.4: enabling device

x86: Fix MSI-X initialization by using online_mask for x2apic target_cpus

found a system where x2apic reports an MSI-X irq initialization
failure:

[ 302.859446] igbvf 0000:81:10.4: enabling device (0000 -> 0002)
[ 302.874369] igbvf 0000:81:10.4: using 64bit DMA mask
[ 302.879023] igbvf 0000:81:10.4: using 64bit consistent DMA mask
[ 302.894386] igbvf 0000:81:10.4: enabling bus mastering
[ 302.898171] igbvf 0000:81:10.4: setting latency timer to 64
[ 302.914050] reserve_memtype added 0xefb08000-0xefb0c000, track uncached-minus, req uncached-minus, ret uncached-minus
[ 302.933839] reserve_memtype added 0xefb28000-0xefb29000, track uncached-minus, req uncached-minus, ret uncached-minus
[ 302.940367] alloc irq_desc for 265 on node 4
[ 302.956874] alloc kstat_irqs on node 4
[ 302.959452] alloc irq_2_iommu on node 0
[ 302.974328] igbvf 0000:81:10.4: irq 265 for MSI/MSI-X
[ 302.977778] alloc irq_desc for 266 on node 4
[ 302.980347] alloc kstat_irqs on node 4
[ 302.995312] free_memtype request 0xefb28000-0xefb29000
[ 302.998816] igbvf 0000:81:10.4: Failed to initialize MSI-X interrupts.

... it turns out that when trying to enable MSI-X,
__assign_irq_vector(new, cfg_new, apic->target_cpus()) can not
get vector because for x2apic target-cpus returns cpumask_of(0)

Update that to online_mask like xapic.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <4A785AFF.3050902@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: Don't use current_cpu_data in x2apic phys_pkg_id

One system has socket 1 come up as BSP.

kexeced kernel reports BSP as:

[ 1.524550] Initializing cgroup subsys cpuacct
[ 1.536064] initia

x86: Don't use current_cpu_data in x2apic phys_pkg_id

One system has socket 1 come up as BSP.

kexeced kernel reports BSP as:

[ 1.524550] Initializing cgroup subsys cpuacct
[ 1.536064] initial_apicid:20
[ 1.537135] ht_mask_width:1
[ 1.538128] core_select_mask:f
[ 1.539126] core_plus_mask_width:5
[ 1.558479] CPU: Physical Processor ID: 0
[ 1.559501] CPU: Processor Core ID: 0
[ 1.560539] CPU: L1 I cache: 32K, L1 D cache: 32K
[ 1.579098] CPU: L2 cache: 256K
[ 1.580085] CPU: L3 cache: 24576K
[ 1.581108] CPU 0/0x20 -> Node 0
[ 1.596193] CPU 0 microcode level: 0xffff0008

It doesn't have correct physical processor id and will get an
error:

[ 38.840859] CPU0 attaching sched-domain:
[ 38.848287] domain 0: span 0,8,72 level SIBLING
[ 38.851151] groups: 0 8 72
[ 38.858137] domain 1: span 0,8-15,72-79 level MC
[ 38.868944] groups: 0,8,72 9,73 10,74 11,75 12,76 13,77 14,78 15,79
[ 38.881383] ERROR: parent span is not a superset of domain->span
[ 38.890724] domain 2: span 0-7,64-71 level CPU
[ 38.899237] ERROR: domain->groups does not contain CPU0
[ 38.909229] groups: 8-15,72-79
[ 38.912547] ERROR: groups don't span domain->span
[ 38.919665] domain 3: span 0-127 level NODE
[ 38.930739] groups: 0-7,64-71 8-15,72-79 16-23,80-87 24-31,88-95 32-39,96-103 40-47,104-111 48-55,112-119 56-63,120-127

it turns out: we can not use current_cpu_data in phys_pgd_id
for x2apic.

identify_boot_cpu() is called by check_bugs() before
smp_prepare_cpus() and till smp_prepare_cpus() current_cpu_data
for bsp is assigned with boot_cpu_data.

Just make phys_pkg_id for x2apic is aligned to xapic.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <4A6ADD0D.10002@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: apic/x2apic_cluster.c x86_cpu_to_logical_apicid should be static

Impact: reduce kernel size a bit, address sparse warning

Addresses the problem pointed out by this sparse warning:
arch/x86/k

x86: apic/x2apic_cluster.c x86_cpu_to_logical_apicid should be static

Impact: reduce kernel size a bit, address sparse warning

Addresses the problem pointed out by this sparse warning:
arch/x86/kernel/apic/x2apic_cluster.c:13:1: warning: symbol 'per_cpu__x86_cpu_to_logical_apicid' was not declared. Should it be static?

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
LKML-Reference: <1239434726.4418.24.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: add x2apic_wrmsr_fence() to x2apic flush tlb paths

Impact: optimize APIC IPI related barriers

Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barri

x86: add x2apic_wrmsr_fence() to x2apic flush tlb paths

Impact: optimize APIC IPI related barriers

Uncached MMIO accesses for xapic are inherently serializing and hence
we don't need explicit barriers for xapic IPI paths.

x2apic MSR writes/reads don't have serializing semantics and hence need
a serializing instruction or mfence, to make all the previous memory
stores globally visisble before the x2apic msr write for IPI.

Add x2apic_wrmsr_fence() in flush tlb path to x2apic specific paths.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "steiner@sgi.com" <steiner@sgi.com>
Cc: Nick Piggin <npiggin@suse.de>
LKML-Reference: <1237313814.27006.203.camel@localhost.localdomain>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: apic: simplify secondary CPU wakeup methods

Impact: cleanup

- rename apic->wakeup_cpu to apic->wakeup_secondary_cpu, to
make it apparent that this is an SMP-only method

- handle NULL ->wak

x86: apic: simplify secondary CPU wakeup methods

Impact: cleanup

- rename apic->wakeup_cpu to apic->wakeup_secondary_cpu, to
make it apparent that this is an SMP-only method

- handle NULL ->wakeup_secondary_cpus to mean the default INIT
wakeup sequence - this allows simplification of the APIC
driver templates.

Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: remove update_apic from x86_quirks

Impact: cleanup

x86_quirks->update_apic() calling looks crazy. so try to remove it:

1. every apic take wakeup_cpu member directly
2. separate es7000_apic

x86: remove update_apic from x86_quirks

Impact: cleanup

x86_quirks->update_apic() calling looks crazy. so try to remove it:

1. every apic take wakeup_cpu member directly
2. separate es7000_apic to es7000_apic_cluster
3. use uv_wakeup_cpu directly

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86: select x2apic ops in early apic probe only if x2apic mode is enabled

If BIOS hands over the control to OS in legacy xapic mode, select
legacy xapic related ops in the early apic probe and shift

x86: select x2apic ops in early apic probe only if x2apic mode is enabled

If BIOS hands over the control to OS in legacy xapic mode, select
legacy xapic related ops in the early apic probe and shift to x2apic
ops later in the boot sequence, only after enabling x2apic mode.

If BIOS hands over the control in x2apic mode, select x2apic related
ops in the early apic probe.

This fixes the early boot panic, where we were selecting x2apic ops,
while the cpu is still in legacy xapic mode.

Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86, apic: move APIC drivers to arch/x86/kernel/apic/*

arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/

x86, apic: move APIC drivers to arch/x86/kernel/apic/*

arch/x86/kernel/ is getting a bit crowded, and the APIC
drivers are scattered into various different files.

Move them to arch/x86/kernel/apic/*, and also remove
the 'gen' prefix from those which had it.

Also move APIC related functionality: the IO-APIC driver,
the NMI and the IPI code.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

show more ...

x86/apic: Add extra serialization for non-serializing MSRs

commit 25a068b8e9a4eb193d755d58efcb3c98928636e0 upstream.

Jan Kiszka reported that the x2apic_wrmsr_fence() function uses

x86/apic: Add extra serialization for non-serializing MSRs

commit 25a068b8e9a4eb193d755d58efcb3c98928636e0 upstream.

Jan Kiszka reported that the x2apic_wrmsr_fence() function uses a plain
MFENCE while the Intel SDM (10.12.3 MSR Access in x2APIC Mode) calls for
MFENCE; LFENCE.

Short summary: we have special MSRs that have weaker ordering than all
the rest. Add fencing consistent with current SDM recommendations.

This is not known to cause any issues in practice, only in theory.

Longer story below:

The reason the kernel uses a different semantic is that the SDM changed
(roughly in late 2017). The SDM changed because folks at Intel were
auditing all of the recommended fences in the SDM and realized that the
x2apic fences were insufficient.

Why was the pain MFENCE judged insufficient?

WRMSR itself is normally a serializing instruction. No fences are needed
because the instruction itself serializes everything.

But, there are explicit exceptions for this serializing behavior written
into the WRMSR instruction documentation for two classes of MSRs:
IA32_TSC_DEADLINE and the X2APIC MSRs.

Back to x2apic: WRMSR is *not* serializing in this specific case.
But why is MFENCE insufficient? MFENCE makes writes visible, but
only affects load/store instructions. WRMSR is unfortunately not a
load/store instruction and is unaffected by MFENCE. This means that a
non-serializing WRMSR could be reordered by the CPU to execute before
the writes made visible by the MFENCE have even occurred in the first
place.

This means that an x2apic IPI could theoretically be triggered before
there is any (visible) data to process.

Does this affect anything in practice? I honestly don't know. It seems
quite possible that by the time an interrupt gets to consume the (not
yet) MFENCE'd data, it has become visible, mostly by accident.

To be safe, add the SDM-recommended fences for all x2apic WRMSRs.

This also leaves open the question of the _other_ weakly-ordered WRMSR:
MSR_IA32_TSC_DEADLINE. While it has the same ordering architecture as
the x2APIC MSRs, it seems substantially less likely to be a problem in
practice. While writes to the in-memory Local Vector Table (LVT) might
theoretically be reordered with respect to a weakly-ordered WRMSR like
TSC_DEADLINE, the SDM has this to say:

In x2APIC mode, the WRMSR instruction is used to write to the LVT
entry. The processor ensures the ordering of this write and any
subsequent WRMSR to the deadline; no fencing is required.

But, that might still leave xAPIC exposed. The safest thing to do for
now is to add the extra, recommended LFENCE.

[ bp: Massage commit message, fix typos, drop accidentally added
newline to tools/arch/x86/include/asm/barrier.h. ]

Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200305174708.F77040DD@viggo.jf.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

x86/apic/x2apic: Fix a NULL pointer deref when handling a dying cpu

Check that the per-cpu cluster mask pointer has been set prior to
clearing a dying cpu's bit. The per-cpu pointer is

x86/apic/x2apic: Fix a NULL pointer deref when handling a dying cpu

Check that the per-cpu cluster mask pointer has been set prior to
clearing a dying cpu's bit. The per-cpu pointer is not set until the
target cpu reaches smp_callin() during CPUHP_BRINGUP_CPU, whereas the
teardown function, x2apic_dead_cpu(), is associated with the earlier
CPUHP_X2APIC_PREPARE. If an error occurs before the cpu is awakened,
e.g. if do_boot_cpu() itself fails, x2apic_dead_cpu() will dereference
the NULL pointer and cause a panic.

smpboot: do_boot_cpu failed(-22) to wakeup CPU#1
BUG: kernel NULL pointer dereference, address: 0000000000000008
RIP: 0010:x2apic_dead_cpu+0x1a/0x30
Call Trace:
cpuhp_invoke_callback+0x9a/0x580
_cpu_up+0x10d/0x140
do_cpu_up+0x69/0xb0
smp_init+0x63/0xa9
kernel_init_freeable+0xd7/0x229
? rest_init+0xa0/0xa0
kernel_init+0xa/0x100
ret_from_fork+0x35/0x40

Fixes: 023a611748fd5 ("x86/apic/x2apic: Simplify cluster management")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191001205019.5789-1-sean.j.christopherson@intel.com

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x86/apic/x2apic: Implement IPI shorthands support

All callers of apic->send_IPI_all() and apic->send_IPI_allbutself() contain
the decision logic for shorthand invocation already and invo

x86/apic/x2apic: Implement IPI shorthands support

All callers of apic->send_IPI_all() and apic->send_IPI_allbutself() contain
the decision logic for shorthand invocation already and invoke
send_IPI_mask() if the prereqisites are not satisfied.

Implement shorthand support for x2apic.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105221.134696837@linutronix.de

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x86/apic: Consolidate the apic local headers

Now there are three small local headers. Some contain functions which are
only used in one source file.

Move all the inlines and dec

x86/apic: Consolidate the apic local headers

Now there are three small local headers. Some contain functions which are
only used in one source file.

Move all the inlines and declarations into a single local header and the
inlines which are only used in one source file into that.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.618612624@linutronix.de

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x86/apic: Cleanup the include maze

All of these APIC files include the world and some more. Remove the
unneeded cruft.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Ac

x86/apic: Cleanup the include maze

All of these APIC files include the world and some more. Remove the
unneeded cruft.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.342631201@linutronix.de

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x86/apic: Use non-atomic operations when possible

Using __clear_bit() and __cpumask_clear_cpu() is more efficient than using
their atomic counterparts.

Use them when atomicity i

x86/apic: Use non-atomic operations when possible

Using __clear_bit() and __cpumask_clear_cpu() is more efficient than using
their atomic counterparts.

Use them when atomicity is not needed, such as when manipulating bitmasks
that are on the stack.

Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Link: https://lkml.kernel.org/r/20190613064813.8102-10-namit@vmware.com

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x86/apic/x2apic: Initialize cluster ID properly

Rick bisected a regression on large systems which use the x2apic cluster
mode for interrupt delivery to the commit wich reworked the clust

x86/apic/x2apic: Initialize cluster ID properly

Rick bisected a regression on large systems which use the x2apic cluster
mode for interrupt delivery to the commit wich reworked the cluster
management.

The problem is caused by a missing initialization of the clusterid field
in the shared cluster data structures. So all structures end up with
cluster ID 0 which only allows sharing between all CPUs which belong to
cluster 0. All other CPUs with a cluster ID > 0 cannot share the data
structure because they cannot find existing data with their cluster
ID. This causes malfunction with IPIs because IPIs are sent to the wrong
cluster and the caller waits for ever that the target CPU handles the IPI.

Add the missing initialization when a upcoming CPU is the first in a
cluster so that the later booting CPUs can find the data and share it for
proper operation.

Fixes: 023a611748fd ("x86/apic/x2apic: Simplify cluster management")
Reported-by: Rick Warner <rick@microway.com>
Bisected-by: Rick Warner <rick@microway.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Rick Warner <rick@microway.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1805171418210.1947@nanos.tec.linutronix.de

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